Windows 10 19H1 is going to RTM in March, and development is starting to wind down. Last week's Fast ring Insider Preview build was the first from the 19h1_release branch, rather than rs_prerelease, which means that 19H2 is on the way to Skip Ahead Insiders soon.
According to Microsoft's Brandon LeBlanc, we're still a few weeks out though.
The timing isn't at all surprising. Last year, it wasn't until February 14 that we got the first Redstone 5 builds. It's only natural that 19H2 will arrive in the same timeframe.
It's completely unclear what features we're going to see in the next feature update to Windows 10, although Microsoft is still promising that Sets is coming. In you're unfamiliar with the feature, it allows the user to group apps into tabs, similar to tabs in a web browser. The company has been very quiet about Sets since it was pulled from Redstone 5 development.
It's also unclear if Microsoft is going to open up the Skip Ahead ring again, or if these builds will only be available to those that are already enrolled. It's likely that they won't have any new features at first, so you won't be missing out on much.